This invention relates to explosive containers. In another aspect, this invention relates to an explosive container for containing cast explosive charges. In still another aspect, this invention relates to an explosive device for delay activated explosives which are to be detonated by a detonating cord. In a further aspect, this invention relates to an explosive device for delay activated explosives which protects against premature detonation of the explosives.
In blasting, it is common to use insensitive explosives or blasting agents such as ammonium nitrate-fuel oil compositions which are detonated by booster or primer charges containing high explosives that are sensitive enough to be detonated by ordinary blasting caps. In blasting operations, it is often advantageous to provide for delayed detonation to control rock fragmentation, rock throw and vibrations. While electric blasting caps have the advantage of precise timing, extraneous electricity from either man-made or natural sources presents a hazard of premature and unwanted detonation of such caps. Therefore, a highly reliable non-electric delay actuated explosive container capable of precise timing and initiating insensitive explosives and blasting agents would be very desirable and advantageous.
While it is necessary for the explosive container to be sturdy enough to resist breakage, from dropping or from the force generated by the detonating cord, for example, the explosive container cannot be cumbersome in design, manufacture and use because economical considerations will prevent its use and acceptance.
Therefore, a need exists for a sturdy and economical container for containing high explosives and a detonator delay unit for the delayed detonation of blasting agents such as ammonium nitrate-fuel oil compositions.